Eloipool or stratum+stratum-mining?

[hahahafr]

Hello,

I'm considering using one of these two software (eloipool or stratum+stratum-mining) to run a heavy stratum mining pool.

My basic concern is performance, which one is more scalable/efficient?

Also the second part of my inquiry is the overall support and resources available (i.e. how much work is needed to implement an Auto_add_user functionality similar to 50BTC) to work with the coinbase distribution and share logging.